The present invention relates to an access device for a surgical treatment which device is used in a surgical operation under an endoscope and for forming an inlet to the inside of a body from the outside thereof.
Today, as a treatment which is known as the surgical treatment of celiac organs, two methods are given; a treatment under a direct observation by means of the sectioning of the abdomen (celiotomy), and the surgical treatment under observation using the endoscope. Although the celiotomy is the most standard treatment method, there arises a problem in that it is required that the abdomen must be largely sectioned in the celiotomy so that the invasion on the side of the patient is large, pains after the treatment prolongs, a long-term hospitalization is required, or anastomosis of the tissue with respect to the sectioned part is generated. On the other hand, the surgical treatment under an endoscope is a treatment in which a treatment device having a long shaft is allowed to pass through a small hole opened in the body while the endoscope image displayed on the monitor is being observed. Consequently, the treatment has an advantage in that the invasion on the side of the patients is small, the treatment is excellent in terms of esthetic aspect, and, at the same time, pains after the treatment are not strong, an early recovery from the damage and an early discharge from the hospital can be made possible. However, from the viewpoint of the surgeon, the surgical treatment under the endoscope requires many techniques such as an operation of forceps and the like. Thus, it is possible to say that the treatment is a method having a considerable peculiarity as compared with the celiotomy. Out of various characteristics, the absence of the tactus constitutes a large factor which makes this treatment method very difficult. For the surgeon in charge of the treatment the tactus constitutes means for obtaining a large amount of useful information on blood vessels and the diagnosis of tissues in the case of tumors or the like which information cannot be obtained in the monitor. The tactus enables the surgeon to administer the treatment in a smooth manner. Thus, it is possible to say that this is a large advantage of the celiotomy.
On the other hand, as a method which compensates for the disadvantages of the two surgical treatments and which doubles the advantages of the aforementioned two surgical treatments, there is proposed a method in which a hand of the surgeon is inserted into an abdominal cavity to treat the abdomen by means of the endoscope with an auxiliary help of the hand of the surgeon. For example, U.S. Pat. No. 5,366,478 discloses a method for holding the air-tight state of the inside of the body at the time of inserting the hand into the body through a transition section or at the time of removing the hand through the transition section from the inside of the body by arranging two donut-shaped balloons inside and outside of the body and swelling the balloons. According to the method, the abdomen can be treated with the inserted hand while a cavity is secured with gas which is sent into the abdomen in the same manner as the conventional surgical treatment under the endoscope. As a consequence, the treatment which cannot be accomplished in the surgical treatment under the endoscope can be administered in a safe manner and in a short time.
Furthermore, U.S. Pat. No. 5,514,133 discloses a method for holding the air-tight state of the body at the time of the insertion and the removal of the hand by sandwiching the abdominal wall with two plates which are connected with bellows, and by arranging a flap valve-shaped valve in a channel which is defined by the two plates. Furthermore, U.S. Pat. No. 5,522,791 discloses a technique for engaging in the air-tight manner a circular elastic member with a sectioned part and, at the same time, providing a sealing member on a sleeve which extends toward the outside from the circular elastic member thereby sealing a sleeve and an arm inserted into the sleeve with this sealing member. Furthermore, PCT WO 96/10963 discloses a technique for providing on a sleeve a first and a second open part which can be closed, and preventing gas inside of the body from leaking to the outside by closing the open parts.
However, in the technique which is disclosed in U.S. Pat. No. 5,366,478, there is provided only one sealing part so that gas leakage is generated at the time of inserting the hand into the body. Besides, in the case where the hand is not inserted into the inside of the body, an inside hole of the donut-shaped balloon must be completely sealed, and it is structurally difficult to hold the air-tight state. Furthermore, there is considered a disadvantage in that the arm is fastened with the balloon, and a cavity to be treated is narrowed down because the balloon is large.
Furthermore, in the technique which is disclosed in U.S. Pat. No. 5,514,133, there is a disadvantage in that the bellows and the valve are located on the sectioned part so that the length of the sectioned part becomes longer than necessary. Furthermore, in this technique, a sufficient space is needed for opening and closing of the flap-shaped valve so that the cavity to be treated is narrowed down as a consequence. Furthermore, this technique has a disadvantage in that the structure thereof is complicated and the setting also becomes troublesome.
Furthermore, in the techniques which are disclosed in U.S. Pat. No. 5,522,791 and PCT WO 96/10963, there is provided a sleeve which extends toward the outside of the body so that there is a problem in that force is received which pushes back the arm constantly to the outside under the pneumoperitoneum, and the pneumoperitoneum pressure abruptly rises by the insertion of the arm into the abdominal cavity. Besides, this technique is structurally difficult, and a very complicated procedure must be taken to put the hand into and out of the body so that the technique is not appropriate in a practical usage.
As described above, in the prior art, it is difficult to completely seal the sectioned part having a large aperture which allows the insertion of the hand. Consequently, it is necessary from now on to consider a peculiar valve structure which is completely different from a valve of a surgical instrument (called trocar) for the conventional surgical treatment under the endoscope.